#define _CRT_SECURE_NO_WARNINGS 

#include <stdio.h>


int main() {
    int a, b, c;
    while (scanf("%d %d %d", &a, &b, &c) == 3) {
        if (a + b > c && a + c > b && b + c > a) {
            if (a == b && b == c)
                printf("Equilateral triangle!\n");
            else if (a == b || a == c || b == c)
                printf("Isosceles triangle!\n");
            else
                printf("Ordinary triangle!\n");
        }
        else
            printf("Not a triangle!\n");
    }
    return 0;
}